Support Runtime Type Validation for JSON Messages

[Matan-Yadaev-Forter]

Currently, @platformatic/kafka only supports compile-time type assertions like jsonSerializer<Person>. However, runtime type validation is becoming a common practice in the TypeScript ecosystem.

It would be great if the library supported runtime validation out of the box, even though it's easy to extend manually.

Here's an example using Zod:

import { Consumer, stringDeserializer } from '@platformatic/kafka';
import { z } from 'zod';

const JsonStringSchema = z
    .string()
    .transform((str, ctx) => {
      try {
        return JSON.parse(str);
      } catch {
        ctx.addIssue({ code: z.ZodIssueCode.custom, message: 'Invalid JSON' });
        return z.NEVER;
      }
    });

const UserSchema = z.object({
  id: z.string(),
  name: z.string(),
  age: z.number(),
});

const userDeserializer = (data: Buffer) => {
  const jsonString = data.toString();

  const result = JsonStringSchema
    .pipe(UserSchema)
    .safeParse(jsonString);

  if (!result.success) {
    console.error('Validation failed:', result.error.issues);
    return;
  }

  return result.data;
};

const consumer = new Consumer({
  deserializers: {
    key: stringDeserializer,
    value: userDeserializer,
  },
});

[mcollina]

It would be great if the library supported runtime validation out of the box, even though it's easy to extend manually.

How would you simplify the above snippet? Something like the following:

import { Consumer, zodValidatorDeserializer } from '@platformatic/kafka';
import { z } from 'zod';

const UserSchema = z.object({
  id: z.string(),
  name: z.string(),
  age: z.number(),
});

const consumer = new Consumer({
  deserializers: {
    key: stringDeserializer,
    value: zodValidatordeserializer(UserSchema),
  },
});